Re: Well pump
Posted by Mike Pick on February 09, 2004 at 08:24:14:
In response to Re: Well pump
: : : : : : My well pump recently went out {after 22 years} and when i replaced it i could not find a 1/3hp 10 gpm pump anywhere. I installed a 3/4hp 10 gpm and now the pump turns on/off 3-4 times when i flush a toilet. I turned the breaker off to the pump and ran all the pressure out of the fawcett. I then measured the PSI on the 15 gallon "pre-charge" pressure tank = 0 psi. The side of the tank said "precharged to 30 psi" so i pumped it up to 30 psi and threw the breaker back on. She pumped back up 50psi on the gauge. The pump still comes on/off 2 times while flushing a toilet. The pressure switch is set fo 30psi on 50 psi off. My question is... Why when i flush a 1.6 gpf toilet does the pump need to come on. Should'nt a 15 gallon tank suffice at least a few flush's? Thank you in advance for you reply and time.
: : : : : The pressure tank usually only holds 25-30 % of the tanks rating. Example; A 20 gallon tank will allow approx.5-6 gallons of water to enter it. A "low flush toilet (1.6 gallon should flush roughly 3-4 times with-out the pump kicking in with a FULL tank.. It seems like an adjustment to the Bladder pressure is required. First ,drain the tank completely (Pump power off),then check what the bladder psi is. Put air in until it is 2 psi below the cut-in pressure. Let us know how you make out. Hube

: : : : Wow. thsnks for the fast reply!!! The marking on the square D pressure switch say 30 on 50 off so i adjusted the precharge as you prescribed from 30 psi to 28 psi. Now the pump kicks on during the 2nd flush{fill up}. Heres my big theory,,, (uh-ohhh)----> even though the switch says it kicks in at 30 psi... according to the gauge it really kicks in around 26 psi. Should i drop the pressure down to 24 psi? I'm not trying to sound lazy but it took me approx 25,0000 pumps with an old bicycle pump to reach 30psi. AGAIN,,,, thank you very much for your advice.
: : : Mike Your better to let some air out (down to 24 lbs.) then IF your pressure gauge is correct, you will operate at 26/46..BUT,if you want to just leave the 28 lbs in ,you can adjust the switch to accomodate this 28 lbs, which will be a 30/50 setting... To make this adjustment, turn the pump power OFF. Remove the switch cover, turn Large nut CW to raise BOTH the cut-in and cut-off pressures. Turn the Small nut CW to raise cut-off ONLY. Probably a 1/2 turn will do it. Check the pressures (power on) after each adjustment. Note; A 30/50 setting is best for most systems. Let us know how you make out. Hube

: : Hey hube,
: : well i adjusted the tank pre-charge down to 24 and nothing changed. Flush the toilet twice and 3/4 of the way thru the second tank filling the pump kicks in. Maybe this is how it used to be. Maybe i'm just more "in-tune" with whats going on now that i've become intimate with it LOL. My well is a "bored" well. Probably 3 feet in diameter and is approx 50 feet down [ at least thats how much pipe i pulled when i swapped out the motor! During last years drought it never thought about drying up. Question--> whould a bigger pre-charge tank solve this issue. My only concearn is a referance table that came with the pump stating approx pump life vs average pump cycles per day. IE higher HP pumps don't like to be cycled per day as many times as lower HP pumps. I replaced my 10 GPM 1/3 hp with a 10 GPM 3/4 hp. Is the extra 1/2 hp the culprit? My current tank is a 15 gallon. Home-Dumpster up the street has a 40 gallon tank, pre-charged to 40psi. Will the bigger tank AND a new switch help out. I just don't want anymore emeranvy's with this house ---> another long story :) I have 2 infants and a stay at home wife. Lots of water gets used around here! :) Thank you for being patient and helping me out.
: : Mike MIKE; it could be your 15 gallon tank is only capable of holding 3 or 4 gallons as you say flushing the toilet twice or less will make the pump kick in. The HD tank that is 40 gallons holds about 10 gallons (check it out). The gallonage of these tanks is very misleading, as they only hold approx 25 % of that in actual water. Also this new 40 (10) gallon one will be more suited to your 3/4 hp, 10 gpm pump.. A pump should be allowed to run AT LEAST a minute on a cycle as this longer run enables the pump to keep its working parts more cool. This 10 gallon tank will allow the pump to run this minute. In a household of 5 or 6 persons, you have no worry about too many cycles in a 24 hour period with a 3/4 hp, 8 or 10 gpm pump. Good luck, Hube


Hi hube,
well i installed the 40 gallon tank and a new pressure switch. My hope was the new pressure switch{ 40/60} would match up better with the new tank and magically solve all my issues. Damm it! i was wrong again and here i am. I could get one flush and the pump would run. My initial pressure on an "empty" fill-up was 58 lbs. The pre-charge tank was set at 38psi. One flush dropped me to 45 lbs and the pump kicked in. SOOO i started adjusting the nuts on the switch. 1/2 a turn here,,,,,,, 1/2 a turn there.....and on and on. I cannot even get close to the 40/60 settings. Roughly i'm getting a 10 psi drop before the pump kicks in. However, thats almost good for 3 flushes. The instructions did not mention any procedure for setting/tweaking the cut in/off. I know i'm way out on the setting's and i need to baseline & start over. Again thx for your time. I know were getting close....Should't be long now :)




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